In probabilistic grammar, we add the concept of probability. Don't worry - it's one of the most simple extensions of CFG that we've seen so far. We will now look at probabilistic context-free grammar (PCFG).
Let's define PCFG formally and then explore a different aspect of it. Refer to Figure 5.9:
Figure 5.9: PCFGs formal definition
Here, T, N, S, and R are similar to CFG; the only new thing here is the probability function, so let's look at that here, the probability function takes each grammar rule and gives us the probability value of each rule. This probability maps to a real number, R. The range for ...
